Guillaume Herincx , was a Belgian Franciscan theologian.
Herincx was born at Helmond, North Brabant.
He became bishop of Ypres. After receiving his preliminary education at 's-Hertogenbosch he entered the University of Louvain, where he devoted himself to the study of the ancient classics and obtained the degree of doctor of philosophy. In 1653 he was appointed lecturer in theology at Louvain.
After fifteen years spent in teaching theology, Father Herincx was honoured with the title of lector jubilate, equivalent to the university degree of doctor of divinity. He was twice elected minister provincial, then definitor general, and finally commissary general for the northern countries of Europe. On 28 April 1677, whilst making a canonical visitation in England, he received word at Newport that Charles II had nominated him Bishop of Ypres.
He was consecrated on 24 October in the same year, in the Franciscan church, Brussels. He left immediately for his diocese but ruled it for less than a year. He died while making his first diocesan visitation.
The epitaph on his tombstone in the cathedral of Ypres says: "Ob virtutem et omnimodam eruditionem ad has infulas assumptus". Letters found in his room after his death show that his promotion to the cardinalate had been determined on by the pope.